RDMA/vmw_pvrdma: Fix reporting correct opcodes for completion

Since the IB_WC_BIND_MW opcode has been dropped, set the correct
IB WC opcode explicitly.

Fixes: 29c8d9eb ("IB: Add vmw_pvrdma driver")
Reviewed-by: Aditya Sarwade <asarwade@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Bryan Tan <bryantan@vmware.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>